Wild Columbine (Aquilegia canadensis) emerging from the shale escarpment along the Mohawk River. Photo by David Behm.
To consider the natural intrinsic qualities of the the Mohawk Towpath Byway corridor you really have to take a geologic perspective.
“Glacial ice and meltwater played a major role in the geologic and landform development of the Mohawk Valley. Prior to the last glaciation, the Mohawk drained south from Schenectady and joined the Hudson River near Coeymans, NY. Following glaciation, this route was buried by glacial sediments and a much larger ‘Iromohawk’ river drained through the valley. For a period of a few hundred years, while the St. Lawrence Lowland was blocked with ice, the Iromohawk conveyed the drainage of the Great Lakes and the meltwater of the eastern Laurentide ice sheet through the valley. The Iromohawk cut wide channels across the Hudson-Mohawk Lowland, deposited cobble-sized gravels in many locations east of Little Falls, and eroded bedrock between Rexford and Cohoes, forming the route the modern river follows today.” – The Mohawk River Action Agenda, NYSDEC, 2012.
If you stand atop the lock 7 dam overlook at the south end of Sugar Hill Road, visualize what this view must have looked like 200 years ago. You would see Goat Island in the middle with rapids cascading down shale bedrock on either side of the island. Many of our present day town roads follow old trails used by Native Peoples. There is reason to believe that Riverview Road follows one of these pre-European historic trails west and Sugar Hill Road follows another north.
One of the more difficult excavations in the eastern Mohawk Valley was necessary along the foot of this escarpment when the original Erie Canal was constructed in 1825. This excavation became known as the “young engineer’s cut.” When enlarging the Erie Canal in 1842 the excavation was also enlarged.
Further west between lock 7 dam and Rexford the Mohawk flows through a deep gorge through shale bedrock. The best place to observe this gorge is from the water level. I recommend a canoe or kayak launched from Mohawk Landing Park on the Clifton Park side of the river or the upper level of Lock 7 Park in Niskayuna or Aqueduct Park also in Niskayuna. To view the gorge from above take a short hike northward along the power lines where they cross the Mohawk Hudson Bikeway between Aqueduct and GE Global Research. Another top down view is along Riverview Road in the vicinity of Nott Road in Rexford, but get out of your car or off your bike and walk Riverview Road along this overlook.
Perhaps my favorite spot for observing geology is from the Cohoes Falls Overlook Park. When the stairway to the lower level is open… the longest stairway in the Byway corridor, hike down to the lower level. From this perspective imagine the discharge of the St Lawrence River coming over these falls and you can visualize what carved the shale cliffs on the other side of the falls.
A geological question: The basalt that forms the lip of the falls… is this resilient geology contiguous with that of the Adirondack Mountains or is it something that defines the northern extent of the Appalachian Mountains? …or neither?
The Byway’s Corridor Management Plan has three paragraphs about our natural resources, perhaps because we didn’t have access to geologic expertise during this period that the document was being formulated. What the Plan does highlight is the broad flood plain between the Lock 7 Dam downstream to the sharp bend in the river west of the I-87 Northway Bridge (also known as the Thaddeus Kosciuszko Bridge). This flood plain has become the Vischer Ferry Nature and Historic Preserve a 600 acre recreational resource on the north side of the river and Lions Park on the south side in Niskayuna through which the Mohawk Hudson Bikeway passes. These flood plains provide the most popular recreational assets within the Byway corridor. But more on that in a subsequent discussion of intrinsic values of the Byway.